In general, many techniques have been used over the years to measure the cutting forces of a blade cutting different materials. For example, the wool felt cutter test measures the force on a blade as the blade cuts through wool felt. This method has worked satisfactorily over the previous years for measuring the force on the blade as the blade cuts through the wool felt. However, the wool felt cutter test is only able to differentiate between blades when the differences in the cutting force exerted on the blades have relatively high measurable differences.
Another drawback with the wool felt cutter test is that it measures the force on the blade. The blade is held in a stationary position with a sensor attached to the blade. The wool felt is then moved across the blade edge to be cut. The sensor detects the force exerted on the blade as the blade edge cuts the wool felt.
In the wool felt cutter test, it is not known how many fibers are actually present in the wool felt. Furthermore, when the test is conducted it is not known how many fibers are actually cut by the blade and how far from the base the fibers have been cut.
Furthermore, in the wool fell cutter, blades have to remain static and dynamic cutting action like a sawing motion cannot be studied.
There is a need to provide a method for measuring the cutting force experienced by the fiber itself as the fiber is cut by a blade.
There is a need to provide a method for measuring the cutting force experienced by a hair as the hair is cut by a blade. Such a method would provide a more accurate measurement of the actual cutting force that is exerted on the hair by the blade during shaving.
There is a need to provide a method for measuring the cutting forces with a relatively high degree of sensitivity in order to determine the differences in the cutting forces between different blades.
There is a need to provide a method for measuring the cutting forces on different types of fibers.
There is a need to provide a method for measuring the cutting forces on hairs having different physiology and/or different chemical or mechanical treatment prior to cutting.
There is a need to provide a method for measuring the cutting force on hairs when the blades oscillate in specific direction, e.g. create a sawing, chopping or scraping movement, or with blades that are heated or electrically charged.